The OP is mistaking filmmaker perspective for world perspective here. The wives are absolutely sexualized by the villains. You don’t dress women in those ridiculous gauze bikini getups unless you’re sexualizing them. The gauze bikinis are in the movie, undeniable.
Neither can you argue that the gauze bikini’s are in the movie for the benefit of a the movie’s male audience. Even when they are literally bathing together, we don’t see any water running down chests while the models arch their backs and run their fingers through their hair and sigh pleasurably. Instead we see a bunch of women perfunctorily rinsing off legs and feet, looking exhausted. When they see max, they take on fearful, closed off expressions, and project fearful, closed off body language.
The movie makes it quite clear both that the villains went out of their way to sexualize these women, and that the filmmakers went out of their way to humanize these same women.
Moreover, the reason Imperator Furiosa is not sexualized by the villains is not because the men don’t objectify women, but rather because Furiosa has taken great pains to make herself genderless under their gaze.
From Entertainment Weekly:
It was Theron herself who unlocked the image of the androgynous warrior—a woman who has escaped the fate of other women by erasing her gender.
“I just said, ‘I have to shave my head,’” Theron recalls. Furiosa is a war-rig operator living in a place where all other females have been enslaved as breeding and milking chattel. But Furiosa is barren and therefore of no value to the despot Immortan Joe and his soldiers. She is considered worthless. ”They almost forget she’s a woman, so there is no threat,” she says. “I understood a woman that’s been hiding in a world where she’s been discarded.” [x]
The reason we don’t hear the villains using the overtly sexist and objectifying language we’re used to hearing in these kinds of movies is not because the villains are “egalitarian oppressors” who objectify all persons equally.
It’s because their perspective is not part of the movie’s narrative. The movie is not told from the point of view of sexist men. The movie is not pandering to an audience of sexist men.
This is a story about sexists, told by non-sexists.
I know it’s a bit confusing, because we’re so used to seeing stories about sexists told by sexists. We’re so used to sexism being portrayed in a certain way, that when it’s portrayed in a different way, it’s hard to recognize.
So let me clear something up – when a man calls a woman a bitch in a movie, that is not the filmmaker’s way of showing the audience he is sexist; that is the filmmaker’s way of showing the audience that his sexist point of view is worth hearing.
I’m gonna say that again:
When a male character calls a female character a bitch in a movie, that is not the filmmaker’s way of showing the audience the character is sexist; that is the filmmaker’s way of showing the audience that the character’s sexist point of view is worth hearing.